Zafar Hayat

Oxidative stability and lipid components of eggs from flax-fed hens: Effect of dietary antioxidants and storage

An experiment was conducted to investigate the effect of dietary antioxidants and storage on fatty acid profile, oxidative stability, and vitamin E concentration of n-3 fatty acid-enriched eggs. Eggs (384, 48/diet) were collected from ISA Brown layers fed diets containing corn-soy (control) with 100 g/kg of flax seed and 2 types of antioxidants [alpha-tocopherols (alpha-TOC) and butylated hydroxytoluene (BHT)] at 0, 50, 100, or 150 IU or mg/kg. Eggs were stored at 4 degrees C. On d 0, 20, 40, and 60 of storage, 2 eggs were selected randomly from each replicate (totaling 12 eggs per treatment) and analyzed. Eggs from hens fed flax had increased alpha-linolenic (18:3n-3), eicosapentaenoic (20:5n-3), and docosahexaenoic acids (DHA, 22:6n-3) and decreased arachidonic acid (20:4n-6) and total n-6:n-3 ratio when compared with control eggs (P<0.05). The n-6:n-3 fatty acid ratio was lowest in the flax+50 IU of alpha-TOC, flax+100 IU of alpha-TOC, and flax+BHT supplemented group when compared with the flax group (P<0.05). With the exception of flax+100 mg of BHT, addition of antioxidants led to a reduction in palmitic acid in fresh eggs (P<0.05). During the first 20 d of storage, over a 17% reduction in total n-3 fatty acids was observed in eggs from flax+50 mg of BHT supplemented groups (P<0.05). Docosahexaenoic acid was the predominant long-chain n-3 fatty acid in egg and was stable during storage in the control, flax, flax+100 IU of alpha-TOC, flax+150 IU of alpha-TOC, and flax+150 mg of BHT groups. However, antioxidant supplementation had no effect on DHA upon storage in flax+50 IU of alpha-TOC and flax+50 mg of BHT eggs where over 13 to 17% reduction in DHA content was observed during 20 to 60 d of storage (P<0.05). Inclusion of alpha-TOC led to over 4.5- to 12-fold increases in alpha-TOC in eggs. Egg storage for 40 d or longer led to over 50% reduction in egg alpha-TOC (P<0.05). Feeding flax seeds led to an increase in TBA reactive substances in eggs (P<0.05). alpha-Tocopherol was better in preventing lipid oxidation than BHT at d 0 of storage. However, neither had a significant effect on egg TBA reactive substances upon 60 d of storage (P>0.05). These studies demonstrate that the level and type of antioxidants and duration of egg storage significantly affected the fatty acid profile, alpha-TOC status, and oxidative stability of chicken eggs.

Long-term effects of feeding flaxseeds on hepatic lipid characteristics and histopathology of laying hens

The long-term effects of dietary flaxseed and tocopherols on hepatic and blood plasma lipids, fatty acids, tocopherols, hepatic TBA reactive substances, and histopathology of Brown Leghorn hens were investigated. Thirty-two-week-old ISA Brown Leghorn hens (n = 120) were kept in cages and were fed 1 of the 3 corn-soybean meal-based diets, a control diet (no flax) or a 10% flax diet with or without 100 IU of tocopherols, until the hens were 64 wk of age. Feeding diets with 10% flaxseed reduced hepatic and plasma fat content, hepatic triglycerides, total number of fat vacuoles, and number of cells with 75% or higher lipid infiltration in hepatocytes (P < 0.05). Addition of tocopherols to the 10% flax diet increased hepatic and plasma tocopherol content. A significant reduction in hepatic TBA reactive substances was observed in the hens supplemented with the basal diet with 10% flax and 100 IU of tocopherols (P < 0.05). Feeding diets containing flaxseed resulted in an increase in the content of alpha-linolenic (18: n-3) and docosahexaenoic acids (22:6n-3), with a concomitant reduction in monounsaturated and saturated fatty acids in the hen liver and plasma. Overall, long-term feeding of hens with flax led to a reduction in liver and plasma lipids and reduced hepatocellular infiltration. Inclusion of tocopherols may be needed to reduce lipid oxidation products in the liver of flax-fed hens. However, tocopherol supplementation had no effect on hepatocellular lipid infiltration or liver total lipid or triglyceride content.

Sensory evaluation and consumer acceptance of eggs from hens fed flax seed and 2 different antioxidants

The sensory attributes and consumer acceptance of eggs from flax seed-fed hens were evaluated by trained and untrained panelists. Hens were fed diets containing 0% flax seed (control), 10% flax seed (flax), 10% flax seed+100 IU/kg of vitamin E (flax+α-tocopherol), or 10% flax seed+100 mg/kg of butylated hydroxytoluene (BHT) (flax+BHT). Fresh eggs collected within 24 h were hard-boiled, coded, and were offered to trained panelists in 4 testing sessions. Sensory traits evaluated were aroma, flavor, off-flavor, and overall difference. The trained panelists rated flax, flax+α-tocopherol, and flax+BHT eggs to be different from control eggs (P<0.001). In a second study, sensory attributes were tested by untrained panelists. The majority (75 to 80%) of the panelists could not distinguish flax seed-fed versus control eggs for aroma and flavor. A consumer preference test was also conducted to gauge end-user response to flax seed-fed eggs. Consumer acceptance testing did not find any significant difference (P>0.05) between control and flax seed-fed eggs. These results suggest that flax seed when incorporated at 10% in the layer diet can produce eggs that are acceptable to untrained panelists and consumers. However, trained panelists are able to detect differences in flavor, aroma, and off-flavor and overall difference in eggs from hens fed flax seed. Antioxidant supplementation (vitamin E, BHT) did not enhance the acceptability of flax seed-fed eggs by trained panelists.

Pomegranate Extracts: A Natural Preventive Measure against Spoilage and Pathogenic Microorganisms

Pomegranate has been known for hundreds of years as a healing food. Health benefits associated with the use of pomegranate are well documented. Research studies have shown that various pomegranate extracts possess great preventive potency against a wide range of pathogenic and spoilage microorganisms, including bacteria, viruses, fungi, and protozoans. Various phytochemical compounds are considered as potent agents responsible for antimicrobial efficacy of pomegranate extracts. These compounds include polyphenols, including hydrolyzable tannins (punicalagin and ellagic acid), anthocyanins, and other polyphenols. The present review investigates the antimicrobial potential of pomegranate fruit extracts against various pathogenic and spoilage microorganisms.

Prevention and Control of Diseases by Use of Pro- and Prebiotics (Synbiotics)

Probiotics are microorganisms (bacteria or yeasts) that can reestablish and recolonize the human intestinal micro flora to give beneficial effect to a host. Prebiotics are the food ingredients that are nondigestible and affect the consumer by encouraging the number and activity of beneficial but selective colonic bacteria. The probiotics perform more efficiently in the presence of prebiotics, with the enhanced beneficial potential of live microorganisms having additional benefits of the prebiotic. Due to the concept, recently much research attention is focused on the combined use of probiotics and prebiotics, generally known as synbiotics, to get their synergistic health properties. This article provides an overview of possible synbiotic combinations, and their mode of action and health benefits upon consumption. In addition, research trends are also elaborated.

Management of diabetic complications through fruit flavonoids as a natural remedy

ABSTRACT Diabetes mellitus is a global disorder, and a major issue for health care systems. The current review outlooks the use of fruit flavonoids as natural remedy in the prevention of diabetes mellitus. The onset of diabetes mainly depends upon genetics and lifestyle issues. Currently used therapeutic options for the control of diabetes, like dietary amendments, oral hypoglycemic drugs, and insulin, have their own limitations. Fruit flavonoids possess various antidiabetic, anti-inflammatory, and antioxidant potentials and act on various cellular signaling pathways in pancreas, white adipose tissue, skeletal muscle, and liver function, which in result induces antidiabetic effects. Recently, antidiabetic effect of fruit flavonoids has been studied using various animal models and clinical trials. Research studies revealed a statistically significant potential of fruit flavonoids in managing the altered glucose and oxidative metabolisms in diabetes. Unlike synthetic antidiabetic agents, fruit flavonoids manage diabetes without compromising cellular homeostasis thereby posing no side effects. Further studies are required in purification and characterization of different fruit flavonoids with respect to their beneficial effect for diabetic patients.

The beneficial uses of glycerin as an alternative energy source in poultry diets

Glycerin or glycerol (C3H5(OH)3) is one of the most valuable and versatile chemical materials known. The term ‘glycerin’ refers in general to a commercial solution of glycerol in water of which the main constituent is glycerol. Glycerin is an odourless, colourless, viscous liquid with a sweet taste. It is completely soluble in both alcohol and water. Glycerin is the main co-product derived from biodiesel production. It is produced by a KOH- or NaOH-catalysed transesterification of the triacylglycerols in fat or oil along with an alcohol. Glycerin is an important ingredient for the production of soaps, cosmetics, pharmaceuticals and food. Additionally, glycerin is highly stable under normal storage conditions, practically non-irritating in its different uses, suitable for interactions with other chemical materials and has no any negative environmental impacts. Nowadays, with increasing glycerin production and its availability on the market, many new and novel uses are expected to be developed, particularly as alternative energy source for poultry diets. Furthermore, glycerin plays an essential role in body cellular metabolism. This review paper discusses the various trials using glycerin in poultry diets as an energy source and its effects on different parameters in the birds. Generally, poultry diets, which included glycerin up to 10% in feed, gave positive responses in most of studies, some of which measured apparent metabolisable energy (AMEn). However, more indices need to be determined in further studies in different poultry species.

Bioconcentration of some macrominerals in soil, forage and buffalo hair continuum: A case study on pasture irrigated with sewage water.

The present study aimed to evaluate the bioaccumulation of some macrominerals in grazing buffaloes fed forage irrigated with sewage water or canal water. In particular, the transfer of sodium (Na), magnesium (Mg), potassium (K) and calcium (Ca) from soil to plant and in turn to animals was evaluated under sub-tropical environmental conditions. Samples of soil, forage and buffalo hair were collected and digested by wet method. Sodium and K concentrations were significantly higher in the soil but lower in the forages; however, Mg and Ca concentrations in both soil and forages were higher. The correlation between soil, forage and hair showed an imbalanced flow of Na, Mg and K and a balanced flow of Ca from soil to forage and then to animals. Based on the findings, the highest rates of transfer of minerals were found for sewage water treatment, whereas lowest rates were found for canal water treatment, except for Na. As the transfer of minerals depends on their bioavailability, the highest values may be due to the high rates of mineral uptake by plants. Thus, the high transfer rate of some elements by plants could become toxic in future causing detrimental effect to grazing livestock.

Evaluation of a natural methionine source on broiler growth performance.

BACKGROUND Methionine, a sulfur-containing amino acid, is essential for the health and growth of broilers, so its optimum level should be provided in broiler diets. Synthetic methionine sources used by poultry nutritionists may cause health hazards in broilers as, during conversion of synthetic methionine to the active form, homocysteine is produced which may be injurious to body tissues when there is a lack of coordination between methyl group donors and acceptors. Thus the present study evaluates the efficacy of a natural methionine source. RESULTS The comparative growth performance of broilers fed synthetic and/or natural methionine was observed. Results revealed that the basal diet has a lower growth performance (P < 0.05) than all other diets. However, replacement of synthetic methionine with a naturally sourced methionine has no significant effect (P > 0.05) on weight gain, feed consumption or feed conversion ratio. Serum biochemistry values and slaughter data also indicated no effect due to two different methionine sources (P > 0.05). CONCLUSION The results of the present study show that synthetic methionine may effectively be replaced with a naturally sourced methionine without affecting the health and growth performance of broilers. However, additional research is needed to further explore other natural sources of methionine.

Comparative ileal digestibility of amino acids in 00-rapeseed meal and rapeseed meal fed to growing male broilers

&NA; Rapeseed meal (RSM) is a commonly used protein source in poultry diet but its usage is limited due to antinutritional factors, the glucosinolates (GLS) and erucic acid. The 00‐rapeseed meal (00‐RSM) is the developed variety of rapeseed with reduced GLS and erucic acid content through genetic selection. The present study was conducted with the objective of comparing the standardized ileal digestibility (SID) of amino acids (AA) in 00‐RSM and RSM when fed to growing broilers. Three samples of each ingredient were collected from different sources. Two hundred and fifty two day‐old male broilers (Hubbard × Hubbard) were fed a corn‐soybean meal based starter diet in crumble form from day 1 to 13. On day 14, all chicks were individually weighed and randomly distributed to 42 replicate pens (6 birds in each pen). Six test diets (2 ingredient × 3 samples) with approximately 20% crude protein were made in mash form in such a way that the 6 test ingredients served as the sole source of AA in one diet. The endogenous AAs (EAA) were determined by feeding a nitrogen‐free diet to six replicate pens. Each test diet was fed to six replicates of broiler chicks from 14 to 21 days of age. Results indicated that the SID of all AA differed (P < 0.001) among 00‐RSM samples. Among RSM samples, the SID of AA varied for arginine, methionine (P < 0.01), histidine, leucine, lysine, aspartic acid, and phenylalanine (P < 0.05). A greater (P < 0.05) SID of all AA except arginine, histidine, phenylalanine, cysteine, and glutamic acid was observed in 00‐RSM compared with RSM. In conclusion, 00‐RSM had greater SID of AA compared with RSM and it is nutritionally superior to RSM to be used in broiler diets.